Open-hearth melting-furnace



(No Model.)

4 SheetsSheet 2. W. SWINDELL. OPEN HEARTH MELTING FURNACE.

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(No Model.) 4 Sheets-Sheet 3.

W. SWINDELL. OPEN HEARTH MELTING FURNACE,

Patented May 7, 1889.

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(No Model.) 4 Sheets-Sheet 4. W. SWINDELL. OPEN HEARTH MELTING FURNACE.

No. 402,782. 7 Patented May 7, 1889.

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11467401 I II V Atty.

UNITED STATES PATENT OFFICE.

WILLIAM SWINDELL, OF ALLEGHENY, PENNSYLVANIA.

OPEN-HEARTH MELTlNG-FURNACE.

SPECIFICATION forming part of Letters Patent No. 402,782, dated May 7,1889. Application filed July '7, 1887. Serial No. 243,696- (No model.)

To all whom it may concern;

Be it known that I, WILLIAM SWINDELL, residing at Allegheny, in thecounty of Allegheny and State of Pennsylvania, a citizen of the UnitedStates, have invented or discovered certain new and useful Improvementsin Open-Hearth Melting-Furnaces, of which improvements the following isa specification.

The invention described herein relates to certain improvements in gasfurnaces for melting metals, and has for its object a construction offurnace wherein the metal may be held in a molten condition as long asdesired away from or outside of the oxidizing influence of thefusing-flame.

Theinvention consists, in general terms, in the construction andarrangement of parts, substantially as hereinafter more fully describedand claimed.

In the accompanying drawings, forming a part of this specification,Figure 1 is a top plan View of the furnace. Fig. 2 is a sectionalelevation of the same on the line 0/; 0:, Fig. 1. Fig. 3 is a horizontalsection on the line y y, Fig. 2. Fig. 4 is a view similar to Fig. 2 onthe line z 2, Fig. 3.

In the practice'of my invention regenerative chambers l and 1, filledwith checkerwork, are constructed in the usual manner, each regenerativechamber being provided with lines 2 and 2, leading from the lower end ofthe chambers and connecting a short distance from the chambers With aflue, 3, leading to the stack 4. (See Figs. 2 and 3.) On suitable piers,5, on the regenerative chambers is built the circular or approximatelycircular hearth 6, provided. with an extension, 7, on one side, and withchargingdoors 8 at suitable points around its circumference. The floorof the hearth is made to incline from the rear and sides toward theextension 7 in which the crucible 9, for the reception of the moltenmetal, is formed. In the end of the extension is formed the tap hole 10,connecting with the crucible at its lowest point, in order that all themetal. may be drawn therefrom.

Outside of the tap-hole is secured a spout or trough,11, for conductingthe metal to a ladle or other receptacle.

In the bottom of the extension, immediately under the crucible, islocated a door, 12, normally held in a closed position by a bar, 13, orany suitable latch, the purpose of said door being to permit of thedischarge of slag, scoria, or other foreign material in the inannercustomary in the ordinary cupola-furnace.

From the upper ends of the regenerative chambers flues 14 and 14 extend,first horizontally, then vertically, and then back horizontally, intothe hearth on each side of the extension 7, as shown in Figs. 1 and 3,said flues entering nearly tangentially with the inner wall of thehearth. Gas-pipes 15 and 15 are inserted through the outer walls of thefines 14 and 14 at a point nearly opposite the entrance of said linesinto the hearth, in order that the gas and air passing along the flues14 and 14 may be thoroughly min gled before entering the hearth. v

Openings 16 and 16 are formed in the flues 2 and 2, (see Fig. 3,) forthe admission of air into the regenerative chambers through said On eachside of these openings 16 and 16 are arranged rails or bars 17, on whichare mounted wheels 18, carrying the ,valveplate 19, adapted toalternately :cover the openings. A chain, 20, connected to each side ofthe valve-plate 19 and passing around the guide-pulleys 21, is attachedto a valveplate, 22, suspended from wheels 23, mounted on bars 24 insuch manner as to move transversely of the fines 2 and 2 and close oneor the other of said flues at a point between the openings 16 and 16 andthe junction of the flues with the main flue The valve-plates 19 and 22are so arranged and connected by the chain 20 that when the valve-plate19 is over the opening 16 the valve-plate 22 will close the flue 2 asagainst connection with the fine 3, and vice versa. This constructionand arrangement of valves permit of the reversal of the operation of thefurnace by the single movement of a lever.

In order to prevent dirt and other foreign material from entering andclogging up the regenerative chambers, I provide pockets 27 at the lowerends of the vertical portions of the fines 14 and 14. [00

In order to heat the regenerative chambers or to maintain heat thereinwhile the hearth is being repaired or a fresh charge of ma terial isbeing placed therein, 1 arrc nge valves 24 and 24 in the fines 14 and 14at a point near their entrance into the hearth, for the purpose ofclosing connection between said flues and the hearth. \Vhen it isdesired to heat the regenerative chambers without heating the hearth thevalves 24 and 24 are closed and one or the other of the fines 2 and 2opened. The gas being ignited in the fine 14 or 14 corresponding to theopen flue leading to the stack, the flame will be drawn down through theregenerative chamber, air for supporting the combustion of the gas being admitted through openings 25 and 25 formed in the fines 14 and 14 atpoints above the entrance of the gas-pipes, (see Fig. 4,) said openingsbeing closed during the normal operation of the furnace by doors 26 and26", as shown. If it is desired to heat both chambers simultaneously,the valves 19 and 22 are placed at a point midway of their movement,thus partially opening both lines 2 and 2, the openings 16 and 16 beingtemporarily covered by a plate or other suitable means.

It will be observed that by reason of the angle at which the fines 14and l4 enter the heart-l1 the flame will pass around the hearth near thewall thereof, and the molten metal in the crucible will not be subjectedto the direct action of the flame, and hence can be held there for anydesired. length of time without excessive oxidation.

One of the prominent characteristics of the invention herein describedis the provision made for the retention of the metal in a moltencondition without subjecting it to the direct action of or contact withthe flame, and thereby avoiding all oxidation of the metal; hence theshape or contour of the hearth may be changed from a true circular form,as shown, to a form more or less oval in horizontal section, or to anyother form, provided the inletflues for the gas and air be so arrangedthat the products of combustion will. not pass di rectly over or inimmediate contact with the molten metal.

Cupola-furnaces having the crucibles or receptacles arranged below thetuyeres, and therefore out of. the line of flow of the fusingflame, areold and well known, as are also furnaces having a receptacle for thereception of the molten metal independent or outside of themelting-hearth, but still in the line of How of the fusing-flame. Noclaim is therefore made herein to such construction, my invention beingprincipally applicable to that class or kind of melting-furnacesemploying a natural draft, and known in the art as airfurnaces with orwithout regenerative chambers.

I claim herein as my invention- 1. An air-furnace for melting metal.having, in combination therewith, a crucible for the reception of moltenmetal located out of the line of flow of the fusing-flame, and combinedgas and air flues entering said furnace in each side of the crucible,substantially as set forth.

2. The combination, in an air-furnace for melting metal, of a circularmelting-hearth, a crucible for the reception of molten metal located atone side of the center of the hearth, and combined gas and air fiuesentering the hearth on each side of the crucible and in a lineapproximately tangential to the wall of the hearth, substantially as setforth.

3. The combination, in an air-furnace for melting metal, of a circularmelting-hearth provided with a lateral extension containing the cruciblefor the reception of molten metal, and combined gas and air fluesentering the hearth 011 each side of said extension andv in a lineapproximately tangential to the wall of the hearth, substantially as setforth.

4. The combination, in an air-furnace for melting metal, of a circularmelting-hearth, a lateral extension from said heart-h containing thecrucible for the reception of molten metal, and a door located in thebottom of said extension under the crucible,substantially as set forth.

I11 testimony whereof I have hereunto set my hand.

/VILLIAM SVVINDELL. Witnesses:

DARWIN S. WoLoorrr, XVILLIAM' REAL.

